Mets starting pitcher Jenrry Mejia delivers to home plate during the first inning of a game against the Washington Nationals. (July 26, 2013) Photo Credit: AP

WASHINGTON -- For so long, he had been the forgotten prospect. Injuries had made it so. He needed Tommy John surgery, and after a comeback that was as brief as it was forgettable, he was sidelined for much of the spring with elbow tendinitis.

Even in the age of saturation coverage and social media, "out of sight, out of mind'' still holds true. How easy it became to forget that before there was Zack Wheeler, before there was Matt Harvey, there was Jenrry Mejia.

"I haven't seen him . . . that good in a long time," Collins said. "The command of his stuff was very, very good -- his location."

Mejia mixed in his slider and changeup, a lethal cocktail when combined with a fastball that appeared to regain the movement that was missing last season when he pitched as a September call-up. That was his first major-league action since elbow surgery in 2011.

Mejia flashed moments of brilliance for the first time since 2010, when he burst on the scene as a 20-year-old with limitless potential.

Word had reached Collins that during Mejia's minor-league rehab stint, he again flashed "plus stuff" and command. Mechanical corrections, Collins said, restored the natural movement on his fastball. And against the Nationals' reeling offense, Mejia brought the scouting reports to life.

Asked if he enjoyed his best day as a big-leaguer, Mejia responded with a wide smile and a question of his own: "What do you think?"

His expression already had given his answer.

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